Papers | Montoya-Castillo Group

Tianchu and Pranay's polariton paper accepted in J. Phys. Chem. Lett.

Sat, 26 Sep 2026 00:00:00 +0000

Congratulations to Tianchu and Pranay for their paper “For molecular polaritons, disorder and phonon timescales control the activation of dark states in the thermodynamic limit,” just accepted in The Journal of Physical Chemistry Letters! With Qiang Shi, they developed a hybrid matrix product state–hierarchical equations of motion approach that simulates polariton dynamics exactly, from a handful of molecules all the way to the thermodynamic limit. This lets them answer how many molecules it takes for collective light–matter behavior to emerge, and shows that disorder and phonon timescales control when and how fast dark/gray states dissipate energy.

Matthew and Srijan's semiclassical dynamics paper out in J. Chem. Phys., an Editor's Pick

Tue, 09 Jun 2026 00:00:00 +0000

Congratulations to Matthew and Srijan for their paper “How to improve the accuracy of semiclassical and quasiclassical dynamics with and without generalized quantum master equations,” just published in The Journal of Chemical Physics and selected as an Editor’s Pick! Semiclassical methods can treat realistic interactions but often lose accuracy. This work uncovers the long sought after mechanism for accuracy improvement when pairing them with generalized quantum master equations — and even shows how to get similar improvements without the generalized master equation. They turn these insights into a protocol for choosing the memory-kernel cutoff, even in previously inaccessible limits, making semiclassical simulations both more accurate and more robust.

Anthony's stochastic cluster expansion paper out in J. Phys. Chem. Lett.

Thu, 16 Apr 2026 00:00:00 +0000

Congratulations to Anthony for his paper “A stochastic cluster expansion for electronic correlation in large systems,” just published in The Journal of Physical Chemistry Letters! Together with Vojtěch Vlček’s group and Libor Veis, the paper introduces a method that recovers near-DMRG-accurate correlation energies for large systems without choosing an active space in advance, opening the door to high-accuracy studies of chemistry in condensed-phase environments.

Tensor-network paper out in J. Chem. Phys.

Sat, 07 Mar 2026 00:00:00 +0000

Tianchu Li, Pranay Venkatesh, and Nanako Shitara — together with Andrés — have published Numerically exact quantum dynamics with tensor networks: Predicting the decoherence of interacting spin systems in The Journal of Chemical Physics (vol. 164, 091103, 2026).

The paper presents an approach for accurate, scalable simulation of decoherence in interacting spin systems — a key step toward predicting how quantum information is lost in realistic environments.

Nanako Shitara's noise-spectroscopy paper out in J. Chem. Phys.

Sat, 14 Feb 2026 00:00:00 +0000

Nanako Shitara, with Andrés, has published Fast, accurate, and error-resilient variational quantum noise spectroscopy in The Journal of Chemical Physics (vol. 164, 061101, 2026).

The work introduces an adaptive approach to quantum noise spectroscopy that delivers higher accuracy with shorter experimental runs — an important step toward making quantum sensors practical in the presence of realistic noise.

Srijan, Tom and Tianchu's CuFeO₂ polaron paper out in J. Phys. Chem. Lett.

Fri, 02 Jan 2026 00:00:00 +0000

Congratulations to Srijan, Tom, and Tianchu for their paper “Coherent and dynamic small polaron delocalization in CuFeO₂,” just published in The Journal of Physical Chemistry Letters! Combining ultrafast experiments from the Cushing, Ginsberg, and Liu groups with our theory, the work shows that small polarons in the photocatalyst CuFeO₂ delocalize coherently and dynamically, and hint at the limits of applicability of a Holstein picture for polaron formation in transition metal oxides.

Tom contributes to "Gerischer electrochemistry today" in ACS Energy Lett.

Tue, 09 Dec 2025 00:00:00 +0000

Congratulations to Tom for contributing to “Gerischer electrochemistry today,” a community Perspective just published in ACS Energy Letters that revisits Gerischer’s framework for charge transfer at semiconductor–electrolyte interfaces and charts open questions for the field.

Srijan and Tom's polaron transport paper out in PNAS

Fri, 09 May 2025 00:00:00 +0000

Congratulations to Srijan and Tom for their paper “Nonequilibrium relaxation exponentially delays the onset of quantum diffusion,” just published in the Proceedings of the National Academy of Sciences! Using memory that is local in both time and space, they predict the exact formation and migration of polarons in one- and two-dimensional lattices of thermodynamic size. They discover that polarons exhibit nonequilibrium anomalous transport and show that polaron motion becomes diffusive only asymptotically in time and system size, and that energy variations can cause localization that current microscopy experiments can observe.

Anthony's Fourier transform teaching paper out in J. Chem. Educ.

Wed, 23 Apr 2025 00:00:00 +0000

Congratulations to Anthony for his paper “A pedagogical tour of the Fourier transform with applications to NMR and IR spectroscopy,” just published in the Journal of Chemical Education! With Nick Cipolla, William Pfalzgraff, Jeffrey Jankowski, and Becky Rapf, Anthony created three self-contained, Python-based lab activities that teach undergraduates the Fourier transform by analyzing audio signals, an IR interferogram, and an NMR free induction decay.

Srijan and Tom's space-local memory Communication out in J. Chem. Phys., an Editor's Pick

Wed, 05 Mar 2025 00:00:00 +0000

Congratulations to Srijan and Tom for their Communication “Space-local memory in generalized master equations: Reaching the thermodynamic limit for the cost of a small lattice simulation,” just published in The Journal of Chemical Physics, and extra congratulations on its selection as an Editor’s Pick! The paper shows that memory can be local in space as well as time, so short simulations of small lattices can exactly predict the dynamics of arbitrarily large systems over long times, cutting the cost of such simulations by orders of magnitude. (It later won the 2025 JCP Best Theoretical Paper by an Emerging Investigator Award.)

Tom's trion Perspective out in J. Chem. Phys., a Featured Article and cover

Fri, 15 Nov 2024 00:00:00 +0000

Congratulations to Tom for the Perspective “Hiding in plain sight: The prevalence and impact of trions and Fermi polarons in transient absorption spectroscopy experiments of 2D semiconductors,” just published in The Journal of Chemical Physics, and extra congratulations on its selection as a Featured Article and the journal cover! Written with the Sambur and Krummel groups, the Perspective offers a unifying explanation of how trions and Fermi polarons shape transient absorption spectra of 2D semiconductors, and shows how different interpretations of the same data lead to different timescales and mechanisms.

Srijan and Tom's polaron transport paper out in Chem. Sci.

Mon, 23 Sep 2024 00:00:00 +0000

Congratulations to Srijan and Tom for their paper “Mori generalized master equations offer an efficient route to predict and interpret polaron transport,” just published in Chemical Science! The work introduces a tool that minimizes the cost of predicting conductivities in small-polaron-forming materials, and a way to map measured conductivities onto polaron energy scales, overcoming the limitations of the phenomenological Drude–Smith model.